Safety cranking device.



A. L SANDBO.

SAFETY CRANKING DEVICE.

APPLICATION FILED MAY 11. 191B.

Patented Dec. 17, 1918.

2 SHEETSSHEET I.

A. I. SANDBO.

SAFETY CRANKING DEVICE.

APPLICATION mu) MAY n 1918.

1,288,443. Patented Dec.17,1918.

2 SHEE1SSHEEI' 2.

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:llnvenrco ANTON-LI. SANDZBO, OF ROCK ISLAND, ILLINOIS.

SAFETY CRANKING- DEVICE.

Appli ca'tion fil'e'd May 17, 1918.

To (ZZZ whom it-mayconc'ern:

Be it-known that I, ANTON I. SANDBo, a citizen ofthe United States,residing at Rock Island; in the county ofRo'ck Island andf-State ofIllinois,- have invented certain new and useful Improvements in SafetyCranking Devices; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as willenableoth'ers skilled" in the art towhich it appertains to make and usethe same.

This invention relates to starting mechanism for the. internalcombustionengines of automobiles, motor boats and in fact any engines-"ofthis-class adapted to bemanually The primary'object-of the invention isto provide'; improved automatically operating safety mechanism fordisengaging the starting crank' from the shaft of the motor in the eventofback'firing of the motor, whereby toprevent injury to the operator.

' A further object of the invention is to simplify-the construction andimprove and insure the practical operation of such mechanism when suchbackfiring takes place, such back firing usually resulting frompremature ignition in the cylinder of the enginez With these objects inview the invention consistsin the im proved construction, arrangement"and combination ofthe partsof the mechanism of the character specified,which will be hereinafter fully described and afterward specificallyclaimed.

In order that theconstruction andoperation thereof may be readilycomprehended, Iliave illustrated an approved embodiment of my'inventionin the accompanying drawings, and willno'w proceed to fullydescribe the same in connection with said drawings, in which 'Figure1rep'resents,.in front end elevation, the starting" crank and theadjacent P 5,

- i Fig. 2,'a transverse, vertical, sectional view -'on';thejplaneindicated by the broken 'line' 2- 2of 'Fig 3, looking in the directionof-the arrow,

Figs-3, mostlya view in side elevation Specification of Letters Patent.

Patented Dec. 17, 1918.

Serial No. 235,117.

showing the parts from the end of the engine shaft to the crank,inclusive, the aut0- mobile spring and its case being shown in section,

Fig. 4, a view similar to Fig. 3, except that all of the parts carriedon the crank and its shaft are shown in section,

Fig. 5, a view, in side elevation,'of the ring which carries the lugsfor engaging in the slots of the release cams,

Fig. 6, a view, in side elevation, of the drum which receives the ringof Fig. 5,

Fig. 7, a detail top plan view of the crank fastener,

Figs. 8 and 9, detail views of the release cams or brackets, and

Fig. 10, a sectional view of a modified drum to be used on a straightshaft.

Like reference characters mark the same parts in all of the figures ofthe drawing.

Referring specifically to the drawing, 12 indicates the end of the shaftof the motor having a diametrically projecting pin 13, which engages theteeth of the usual ratchet 14', secured by a pin 14 to the end of theshaft 15 of the starter, during the operation of starting the engine inthe usual manner by turning the attached starter crank 16, the startershaft 15 being normally pressed into position with relation to theengine shaft by a spring 17 surrounding said shaft 15' the shaft beinginclosed in a cylinder 18 against which one end of the spring inclosedin a sleeve 19, engages, while the other end presses against a ring 20secured around the shaft 15 to hold said shaft away from the engineshaft with the teeth of the ratchet 1 1- clear of and out of the line ofthe pin 13.

21 indicates the front cross bar of the chassis which is formed withopen bottom to receive a spring 22 which is held in the cross bar by theclamps 23 and nuts 24L, 25. The nuts 25 also clamp in position therelease brackets 26 and 27 the stems 28 of the clamps 23 on which thenuts are threaded passing through openings 29 in the horizontal flanges30 of the brackets 26 and 27.

On the starter crank shaft 15 is a drum 31 (see-Figs. 3, 4i and .10)secured by screws 32- 'to said shaft, and serving to receive screws 33by which the crank fastener 34 is held tight against the drum, thefastener having a curved wedging inner surface 35 which, when the screws33 are tightened up serves to bind these parts tightly to the crankshaft.

The drum 31 is surrounded by a ring 36, and has in its outer peripheralsurface a series of cups 37, the ring having in its inner surfacesubstantially triangular shaped pockets 38 opposite said cups, a ball 39being loosely placed in each of said pockets.

Any desired number of pockets may be used as at the left of Fig. 2, andthe remainder of the drum recessed to reduce its weight and balance thesame, as at the right of said figure.

WVith this construction, when the crank is turned to the right, theballs will roll up into the larger upper ends of the pockets and therebyrelease the drum and ring but in case the engine back fires, or for anyother reason the crank is turned to the left, the balls will drop intothe shallow ends of the pockets and cause the drum and ring to turntogether.

The release brackets 26 and 27 are provided with curved bodies 40 inwhich are slots 41 in which are seated lugs 42 on the backward by theengine shaft.

The utility and simplicity of my invention will be evident from theforegoing and I desire to be understood that changes and variations maybe made from the specific construction described, without departing fromthe spirit and scope of the invention.

Having thus fully described my invention, what I claim as new and desireto secure by Letters Patent of the United States is 1. The combinationwith the front bar of the chassis and the crank shaft of a starter, ofrelease brackets secured to the chassis bar and provided with inclinedslots, a ring surrounding the crank shaft and provided with lugsengaging in said slots, and means for releasing said engagement when theshaft is turned backward or to the left, as by back firing of theengine.

2. The combination with the front bar of the chassis and the crank shaftof a starter, of .release brackets secured to the chassis bar andprovided with inclined slots, a ring surrounding the crank shaft andprovided release.

with lugs engaging in said slots, and means for releasing saidengagement when the shaft is turned backward or to the left, as by backfiring of the engine, said releasing means comprising a drum within thering provided with exterior pockets in its periphery, interiortriangular pockets in the ring, with their narrow ends to the left, andballs which wedge down into said narrow ends causing the ring and drumto rotate together with the shaft thus forcing the'lugs of the ring totravel in the inclined slots of the release brackets and force the shaftrearwardly in case of back firing. Y

3. The combination with the engine shaft having a lateral pin, a startercrank shaft having a ratchet at its forward end, a spring normallymaintaining the ratchet in engagement with the pin to cause the engineshaft to be turned to the right when the starter crank is so turned, thechassis rear bar, release brackets secured to said bar and havinginclined grooves, a drum on the crank shaft,

. turning therewith, and having exterior peripheral pockets, a ringaround the drum having tr angular pockets narrowing tothe left, lugs onthe ring engaging in the slots of the release brackets, and balls in thecups and pockets which remain in the wider parts of the pockets when thecrank shaft is turned to the right and permits the drum to rotate withthe shaft without carrying the ring with it, the balls wedging into thenarrow ends of the pockets. whenthe'shaft and drum are turned to theleft carrying the ring and its lugs with it,'thus withdrawing thestarter shaft ratchet from engagement with the pin of the engine shaft.4. The combination with a starter crank shaft, of a drum securedthereon, andna crank fastener disposed upon said shaft to extend betweenthe drum and shaft and. secured to said drum. 5. The combination with astarter crank shaft, of a drum secured thereon, a crank fastener havinga curvedwedging inner surface disposed to extend between said drum andshaft, and means for securing said fastenerto said drum. v I 6. Thecombination with a support and an engine cranking shaft, of a brackethaving an inclined slot, a lugprojecting into said slot, one of saidparts being mounted to rotate with the cranking shaft and disposed toimpart an axial movement thereto and the other. being stationary, andmeans for throwing the cranking shaft outwardly upon its 7. Thecombination with a fixed support shaft whereby the ring will rotatewithithe cranking shaft in one direction, release name to thisspecification in the presence of brackets each havin an inclined slot,lugs two subscribing witnesses.

projecting into sai inclined slots, one of said two last named elementsbeing station- ANTON SANDBO" 5 ary and the other movable disposed to im-Witnesses:

part an axial movement to said shaft. CARL J. Mfrom,

In testimony whereof I have signed my CARL KI'iHL.

Copies of this patent may be obtained for five cents each, by addressingthe "Gommissioner oi Iatentn, Washington, D. 0.

